IR3081A Datasheet, PDF (1/39 Pages) International Rectifier – XPHASETM VR 10 CONTROL IC

IR3081A
DATA SHEET
XPHASE^TM VR 10 CONTROL IC
DESCRIPTION
The IR3081A Control IC combined with an IR XPhase^TM Phase IC provides a full featured and flexible way
to implement a complete VR 10 power solution. The “Control” IC provides overall system control and
interfaces with any number of “Phase ICs” which each drive and monitor a single phase of a multiphase
converter. The XPhase^TM architecture results in a power supply that is smaller, less expensive, and easier
to design while providing higher efficiency than conventional approaches. The IR3081A is intended for
VRD 10 or VRM/EVRD 10 applications that use external VCCVID/VTT circuits.
The IR3081A is functionally equivalent to the IR3081, but incorporates the following modifications:
• Under Voltage Lockout start threshold increased from 9.1V to 9.7V (typical) and hysteresis increased
from 200mV to 800mV (typical).
• Hysteresis (52mV typical) added to the SS/DEL comparator to prevent Power Good output chatter.
• Over current discharge current increased from 6uA to 40uA (typical) to reduce the over current delay
time.
• IIN pin precondition circuit added to disable current sharing in the phase ICs during soft start.
FEATURES
• 6 bit VR 10 compatible VID with 0.5% overall system accuracy
• 1 to X phases operation with matching phase ICs
• Programmable Dynamic VID Slew Rate
• No Discharge of output capacitors during Dynamic VID step-down (can be disabled)
• +/-300mV Differential Remote Sense
• Programmable 150kHz to 1MHz oscillator
• Programmable VID Offset and Load Line output impedance
• Programmable Softstart
• Programmable Hiccup Over-Current Protection with Delay to prevent false triggering
• Simplified Powergood provides indication of proper operation and avoids false triggering
• Operates from 12V input with 9.1V Under-Voltage Lockout
• 6.8V/5mA Bias Regulator provides System Reference Voltage
• Enable Input
• Small thermally enhanced 28L MLPQ package
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